Ziprasidone outcome and tolerability: a practical clinical trial with plasma drug levels

The use of ziprasidone in clinical practice: Analysis of pharmacokinetic and pharmacodynamic aspects from data of a drug monitoring survey

This study related clinical effects to daily doses and serum concentrations of ziprasidone by retrospective analysis of data from a therapeutic drug monitoring (TDM) survey established for patients treated with the new antipsychotic drug. In the total sample of 463 patients ziprasidone doses ranged between 20 and 320 mg/d and correlated significantly (r2 = 0.093, P < 0.01) with serum concentrations. The latter were highly variable within and between individual patients (between patients median 67 ng/ml, 25–75th percentile 40–103 ng/ml). Pharmacokinetic interactions with comedication played a minor role. According to the clinical global impressions (CGI) scale most of the 348 patients who were under antipsychotic monotherapy with ziprasidone were either much or very much improved (43.3 and 17.3%, respectively). The previously proposed therapeutic range of 50–130 ng/ml ziprasidone in serum or plasma, which can in effect be used interchangeable, was confirmed. In patients who were at least much improved and defined as “responders” mean serum concentrations of ziprasidone were 80 ng/ml and 78 ng/ml in patients who did not reach this improvement score. In patients with serum levels above or below 50 ng/ml, the number of responders was 66 or 63%, respectively. The difference between the two groups was not significant (P = 0.375), and improvement or side effects did not correlate significantly (P > 0.05) with doses or serum levels. It is concluded that TDM of ziprasidone may be useful for treatment optimization because of highly variable serum concentrations resulting under therapeutically recommended doses of the drug.

Almost all antipsychotics result in weight gain: a meta-analysis

Introduction

Antipsychotics (AP) induce weight gain. However, reviews and meta-analyses generally are restricted to second generation antipsychotics (SGA) and do not stratify for duration of AP use. It is hypothesised that patients gain more weight if duration of AP use is longer.

Method

A meta-analysis was conducted of clinical trials of AP that reported weight change. Outcome measures were body weight change, change in BMI and clinically relevant weight change (7% weight gain or loss). Duration of AP-use was stratified as follows: ≤6 weeks, 6–16 weeks, 16–38 weeks and >38 weeks. Forest plots stratified by AP as well as by duration of use were generated and results were summarised in figures.

Results

307 articles met inclusion criteria. The majority were AP switch studies. Almost all AP showed a degree of weight gain after prolonged use, except for amisulpride, aripiprazole and ziprasidone, for which prolonged exposure resulted in negligible weight change. The level of weight gain per AP varied from discrete to severe. Contrary to expectations, switch of AP did not result in weight loss for amisulpride, aripiprazole or ziprasidone. In AP-naive patients, weight gain was much more pronounced for all AP.

Conclusion

Given prolonged exposure, virtually all AP are associated with weight gain. The rational of switching AP to achieve weight reduction may be overrated. In AP-naive patients, weight gain is more pronounced.

Remission in schizophrenia: 196-week, double-blind treatment with ziprasidone vs. haloperidol

To compare the remission rate and its time-course over 196 wk of double-blind treatment with an atypical antipsychotic, ziprasidone (80-160 mg/d given b.i.d., or 80-120 mg/d given q.d.), or a conventional antipsychotic, haloperidol (5-20 mg/d). Outcome assessments included attainment of remission (Andreasen criteria) by longitudinal analysis. Positive and Negative Syndrome Scale (PANSS) scores, Global Assessment of Functioning Scale (GAF) scores, and quality-of-life (QLS) were also assessed in the initial 40-wk study phase (n=599) and the 3-yr extension study (n=186). Discontinuation rates in the initial 40-wk core and follow-up extension studies were comparable between groups: 64% and 65% for the 80-160 mg/d ziprasidone group, 65% and 58% for the 80-120 mg/d ziprasidone group, and 60% and 66% for the 5-20 mg/d haloperidol group, respectively. Mean change scores from baseline to LOCF endpoint (week 40 or early termination) for PANSS negative and GAF (primary efficacy variables) were not statistically significantly different between ziprasidone and haloperidol. During the 3-yr extension study, ziprasidone-treated subjects (80-160 mg/d) were more likely to achieve remission (51%) than haloperidol-treated (40%) subjects (p=0.04), while there was a favourable trend associated with 80-120 mg/d ziprasidone (48%). Compared to the haloperidol group, subjects assigned to the 80-160 mg/d ziprasidone group showed a gradual and persistent improvement in remission (p=0.006) and quality-of-life (p=0.004) in the longitudinal analyses. Significant differences in the trajectory of PANSS total and GAF scores favouring the 80-160 mg/d ziprasidone group were also observed. In this long-term, double-blind study, ziprasidone treatment was more likely to result in remission than haloperidol treatment, and was associated with greater improvement in quality-of-life.